Grate-bar



(No Model.)

D. U'. CORY.

f GRATE BAR.y

No. 433,519. Patented Aug. 5, 1890 f l UNITED STATES PATENT OEEIcE.

DAVID U. OORY, OF ENGLEWOOD, NEW JERSEY.

G RAT E-BAR.

SPECIFICATION forming part of Letters Patent No. 433,519, dated August 5, 1890.

Y Application filed January 8, 1390. Serial No. 336,306. (No model.) p

To all whom `it may concern:

Be it known that I, DAVID U. OORY, of Englewood, in the county of Bergen and State of New Jersey, have invented a new and useful Improvement in Grates, of which the following is a specification. Y l

The invention relates to grates for stoves and furnaces, the primary object being to provide an effectual means for cleaning the fire.

To this end the invention consists, primarily, in the combination of rotating bars with alternate stationary bars, the rotating bars preferably being made hollow from end to end to permit a iiow of cold air through them, and being provided externally with a screwthread or with .other inequalities, and the stationary bars being so shaped and arranged that their upper surfaces will be about on a level with the axes of the rotating bars.

The invention is illustrated in the accompanying drawings, in which- Figure l is a plan of the grate-surface of a furnace, one of the bars being shown in section and the area of the lower end of the lirepot being indicated by the dotted line m m. Fig. 2 is a verticallongitudinal section on the line n n of one of the bars and the connected gear, Fig. 3 being a cross-section of one of the bearings of this bar, taken on the line o o; Fig. 4 is a vertical crosssection of the three bars shown in Fig. l, taken on the line o' r of said figure. Fig. 5 is a modied construction of a bar in which the exterior is provided with bosses or detached prominences in lieu of the continuous thread shown in Fig. l.

The construction and mounting of the individual rotating bar in the preferred form is shown in Fig. 2, in which the hollow bar A is shown as supported by the two bearings B and O. The end which rests in the bearing B is fixed against longitudinal movement; but the other end is provided with a cylindrical recess, so as to fit easily over the cylindrical bearing C, that projects from the fixed frame D. This construction of the bearings compensates for the changes in length which the bar undergoes with changes of temperature. One end of the bar is slotted, as at e, this slot communicating Wit-h the hollow interior of the bar, and the bearing C is also made hollow and open to the air at its under side. As both of the openings are outside the limits of the fire, provision is thus Inade for a constant stream of cold air to flow through the bar along the entire length which is exposed to the direct heat of the fire. This operates to keep the bar from becoming overheated, and from this it follows that the bar, which is already strong by reason of its tubular form, is prevented from warping and becomingdistorted, as would be the case if it were made solid.

Referring to Fig. l, there is seen a system embracing three of these rotating bars A A, arranged in the frame D. Between the rotating bars are arranged the stationary bars F F, which preferably are made with crosssection, as shown in Fig. 4..

The rotating bars preferably are cylindrical,

` and are provided with a coarsesquare thread.

Vhen the bars are rotated, (which may be effected by means of a crankG introduced into a square mortise in their ends,) the spent coal and clinker will be caught between the sharp edges of the stationary bars `and the threads of the rotating bars, and by the shearing action thus produced will be easily comminutcd, so as to drop through into the pit. The action of the threads on the rotating bars is such as also to thoroughly agitate the mass of the tire, and thus free it of the fine ashes.

The stationary bars, as shown in Fig. et, are so arranged that their upper surfaces are about on a level with the axes of the rotating bars. This is found in practice to give much better results than when the stationary bars rise to the level of the top of the rotating bars. In the latter case the clinker is much more like to clog between the two sets of bars7 and the cutting action is much less perfect.

While I prefer to provide the exterior of the bars with continuous threads, l do not propose to limit myself under all circumstances to such construction.

Rotating cylindrical bars with other forms of projection will be found efficient in agitat- Ving a fire and freeing it from ashes and dead coal. One such form` is shown in Fig. 5, in

which the projections are in the form of simple studs shown as arranged in a spiral.

The rotating bars maybe constructed so as to be turned separately by the application of IOO the crank (or other instrument) to each in succession; or they may be connected by means of gears, as shown at H Hin Figs. l

and. 4, in which case the movement of one will impart a corresponding movement to the others.

While I prefer always to ventilate my rotating bars in the manner shown, yet itis believed that the rotating bar provided With an external thread or other prominenoes will be found of much advantage, even if the body of the bar were to be madesolid. I therefore reserve to myself the right to make them in this Way, if at any time it should be found desirable.

I do not claim to be the first to propose the use of rotating grate-bars, nor the first to construct such bars With a spiral or augershaped exterior, nor the first to make gratebars hollow, so as to provide for the flow of a Cooling-Huid through them.

rlhe combination of rotating grate-bars With alternating stationary bars, the upper surface of the latter being arranged substantially on 2 5 a level with the axes of the former.v

DAVID U. CORY. Witnesses:

RoBT. F. GAYLoRD, FRANK B. MURPHY. 

